<p>This study presents a two-dimensional dynamic model and calibrated model-experiment comparison for a macroscopic microrobot proxy undergoing oblique impacts in simplified rigid viscous channels. Motivated by biomedical microrobotic applications, the complex in vivo environment is intentionally reduced to a controlled macroscale system consisting of a single 3&#xa0;mm steel bead moving in a straight, rigid channel filled with static water or operated in air. The proxy particle motion is divided into three phases: free motion, oblique contact with the upper wall, and oblique contact with the lower wall. Dynamic models for these phases are established using the Newton–Euler equations. The working-fluid resistance in the static-water experiments is represented by two empirical effective damping coefficients governing translational and rotational motion which are calibrated for the present proxy system. Normal and tangential contact forces between the proxy particle and the rigid channel walls are calculated using a viscous contact force model together with Coulomb friction, accounting for relative tangential slip during impact. Because the dynamic response is sensitive to the incident angle, two angles, 18° and 60°, are examined. The calibrated model reproduces the measured trajectories and velocity trends under the tested conditions, supporting its use for describing the collision and damping dynamics of the macroscopic proxy system. A comparison between motion in static water and in air further illustrates the role of working-fluid damping in suppressing lateral and rotational motion. The results provide a controlled physical basis for studying oblique impact and effective damping mechanisms relevant to microrobot-inspired confined motion.</p>